﻿/*
 * Copyright (c) 2009, Thiago M. Sayao <thiago.sayao@gmail.com>
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without 
 * modification, are permitted provided that the following conditions are met:
 *  * Redistributions of source code must retain the above copyright notice, 
 *    this list of conditions and the following disclaimer.
 *  * Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 *  * Neither the name of the author nor the names of its contributors may be 
 *    used to endorse or promote products derived from this software without 
 *    specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
 * POSSIBILITY OF SUCH DAMAGE.
 */

using System;
using System.Web;
using System.IO;
using System.Drawing;
using System.Drawing.Imaging;
using System.Globalization;
using DotNetBurner.Model;
using DotNetBurner.Web;

namespace DotNetBurner
{
    public class VoteImageHandler : IHttpHandler
    {
        public void ProcessRequest(HttpContext context)
        {
            var response = context.Response;
            string url = context.Request["url"].Trim();

            int voteCount = new CachedRepository(SwissKnife.ConnectionString).GetVoteCountByUrl(url);

            string key = String.Concat("img-burn-", voteCount);
            
            byte[] data;

            if (!context.Cache.TryGet(key, out data))
            {
                string path = HttpContext.Current.Server.MapPath("~/Cache/Buttons");
                string fullpath = String.Format(CultureInfo.InvariantCulture, "{0}/burn-{1}.png", path, voteCount);

                FileInfo file = new FileInfo(fullpath);

                if (!file.Exists)
                {
                    //image does not exists, generate!
                    ImageGenerator gen = new ImageGenerator();

                    using (Image img = gen.Generate(voteCount))
                    {
                        img.Save(fullpath, ImageFormat.Png);
                    }
                }

                using (MemoryStream memoryStream = new MemoryStream((int)file.Length))
                {
                    using (FileStream fs = file.Open(FileMode.Open, FileAccess.Read, FileShare.Read))
                    {
                        int buffSize = Convert.ToInt32(Math.Min(file.Length, 8*1024));
                        byte[] buffer = new byte[buffSize];

                        int bytesRead;
                        while ((bytesRead = fs.Read(buffer, 0, buffSize)) > 0)
                        {
                            response.OutputStream.Write(buffer, 0, bytesRead);
                            memoryStream.Write(buffer, 0, bytesRead);
                        }
                    }

                    data = memoryStream.ToArray();
                }

                context.Cache.CacheData(key, "VoteButton", data);
            }
            else
            {
                response.OutputStream.Write(data, 0, data.Length);
            }

            response.ContentType = "image/png";
            response.OutputStream.Flush();

            context.CacheResponse(TimeSpan.FromMinutes(DotNetBurnerSettings.Settings.VoteImageCacheDuration));
        }

        public bool IsReusable
        {
            get
            {
                return false;
            }
        }
    }
}
